Cutting steel, with a pneumatic chisel takes a lot of skill. Almost as much as using a hand burin. The difference is in the effort.
On the other hand, a laser evaporates steel. A burin or chisel, makes a cut. That is one of the reasons why laser engraving is so flat. The other reason is that in hand engraving, normally the background is removed, lowered by removing material. A laser can do it too. But it cannot do a cut..and it can not dot the background by punching it.
Doing a cut in the steel , developing a burr, is, in short, totally different to drawing in the steel evaporating it.
The revolver you are showing was hand engraved in some areas like the back of the frame over a previously laser engraved pattern, like in the back part of the frame.
The background of the scrolls in the cylinder has also being hand punch dotted after the scroll was laser engraved. So it is a laser engraved/ hand improved engraving.